Quizzed on his remarks this morning, he told BBC Radio 4's Today programme: "We think the risks as we explained them to the students were justified. Had we had any suggestion that lives were at risk or anything approaching that...then we wouldn't have gone anywhere near this."

He pointed out that a risk assessment had been carried out and "we got as good a sense as we could of what the risks were and our assessment was at most the risk was deportation."

The students were orally warned three times of the risk of arrest, deportation and not being allowed to return to the country, he said.

He denied the briefing of the students had been "shambolic", insisting they had been repeatedly spoken to individually and as a group. It would not have made any difference if they had been given a warning in writing instead, he argued.

"The important thing we have to hold on to here is the public interest there is in showing that film," he added.

But Professor George Gaskell, pro-director at the London School of Economics, said the university authorities were unaware until last week that the BBC had used a 10-person party as cover for an eight-day trip by Panorama to the country.

The professor said that had veteran journalist John Sweeney been caught, the party - which included an 18-year-old student - could have found themselves held in solitary confinement in a North Korean prison.

The BBC has become embroiled in a row with the LSE after an undercover team used a student visit to North Korea to film a documentary about the state. Photo: GETTY

Students were not told that an additional two-man film crew would be joining them on the trip until they arrived in Beijing, en route to Pyongyang.

Three students have since complained and the BBC has agreed to pixelate their images.

Prof Gaskell also warned that the situation could now jeopardise the work of its academics in other sensitive parts of the world.

Sir Peter Sutherland, the LSE chairman, agreed, arguing that the School’s reputation depended on its “integrity throughout the world”.

He told Today: “We have academics and students all over the world on trips in sensitive parts of the world and they would definitely be put at risk.

“If academics can’t go to any part of the world on the basis of trust in terms of what they say they're doing and what they're about, this undermines the integrity of the institution.”

One member of the party who travelled to North Korea wrote to the LSE's student newspaper, The Beaver, to say they had not been informed by the BBC of the risks, the Times reported.

The anonymous student said: "Contrary to what the BBC spokesperson insists, I have never been informed of the risks that I faced being in North Korea with the one print journalist who I agreed to travel with.

"I was never told that I could be held in detention or that I risked not being able to return to the country.

"Furthermore, because we were informed that there are only two flights out of Pyongyang to Beijing per week, we would not have been able to leave even if we had insisted on no longer being part of the trip, as the nature of what we had consented to changed.

"Because most of the consenting was done in private, conversations between a student and Tomiko (Mr Sweeney's wife) or Alexander (the other BBC journalist), what each student consented to varies."

Another student wrote on Facebook that she was fully aware of the risks however, and accused the LSE of blowing the affair out of proportion.

Nicola Dandridge, chief executive of Universities UK, said she would be seeking to discuss the situation with the BBC to ensure it understood the concerns of the university sector.

She said: "We are concerned about the methods used in making this programme. Universities must be able to work with integrity and operate in sensitive areas of the world.

"The UK's academics have a global reputation, and it is vitally important that they can be trusted and seen to be working in an open and transparent manner.

"The way that this BBC investigation was conducted might not only have put students' safety at risk, but may also have damaged our universities' reputations overseas."